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packages/quiver/test/iterables/min_max_test.dart

+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+library quiver.iterables.min_max_test;
+
+import 'package:test/test.dart';
+import 'package:quiver/iterables.dart';
+
+main() {
+  group('max', () {
+    test('should return the maximum element', () {
+      expect(max([2, 5, 1, 4]), 5);
+    });
+
+    test('should return null if the iterable is empty', () {
+      expect(max([]), null);
+    });
+  });
+
+  group('min', () {
+    test('should return the minimum element', () {
+      expect(min([2, 5, 1, 4]), 1);
+    });
+
+    test('should return null if the iterable is empty', () {
+      expect(min([]), null);
+    });
+  });
+
+  group('extent', () {
+    test('should return the max and min elements', () {
+      var ext = extent([2, 5, 1, 4]);
+      expect(ext.min, 1);
+      expect(ext.max, 5);
+    });
+
+    test('should return the single element', () {
+      var ext = extent([2]);
+      expect(ext.min, 2);
+      expect(ext.max, 2);
+    });
+
+    test('should return null if the iterable is empty', () {
+      var ext = extent([]);
+      expect(ext.min, null);
+      expect(ext.max, null);
+    });
+  });
+}